US bridges old, risky and rundown

Cracked concrete exposes parts of reinforcement bars on the Frederick Douglass Memorial Bridge which spans the Anacostia River in Washington on Wednesday, Sept. 4, 2013. The bridge, which carries more than 70,000 vehicles a day, was designed to last 50 years. Its now 13 years past its life expectancy. An Associated Press analysis of 607,380 bridges in the most recent federal National Bridge Inventory showed that 65,605 were classified as "structurally deficient" and 20,808 as "fracture critical," making them higher risk bridges. (AP Photo/Alex Brandon)

Alesia Tisdall stands for a photograph under the Frederick Douglass Memorial Bridge which spans the Anacostia River in Washington on Friday, Sept. 6, 2013. Tisdall, who drove daily over the bridge for 15 years but now crosses it only occasionally, said she found it unnerving that the bridge would "bounce" in the middle as she sat in bumper-to-bumper traffic. "Youd look at the person sitting next to you like, 'Did you feel that bounce?' And theyd be looking back at you like they were thinking the same thing," said Tisdall, 50, a computer systems specialist at the Justice Department. (AP Photo/Alex Brandon)

The Washington Monument stands behind the Frederick Douglass Memorial Bridge which spans the Anacostia River in Washington on Wednesday, Sept. 4, 2013. An Associated Press analysis of federal data found 7,795 bridges around the country, including this one, in significant disrepair and at risk of collapse should a single, vital component fail - a combination of red flags that experts say is particularly problematic. (AP Photo/Alex Brandon)

A "catcher beam" is seen under the Frederick Douglass Memorial Bridge which spans the Anacostia River in Washington on Wednesday, Sept. 4, 2013. Worried about the possibility of a catastrophic failure, the District of Columbias Department of Transportation has inserted "catcher beams" underneath the bridges main horizontal beams to prevent the bridge from falling into the river should one of the main components give way. (AP Photo/Alex Brandon)

Don Britton casts his fishing rod line under the Frederick Douglass Memorial Bridge which spans the Anacostia River in Washington on Friday, Sept. 6, 2013. The bridges steel underpinnings have thinned over time, and there is rust, corrosion and crumbling concrete. (AP Photo/Alex Brandon)

ADVANCE FOR USE MONDAY, SEPT. 16, 2013 AND THEREAFTER - This Thursday, Sept. 12, 2013 photo shows rust on the underside of the Chestnut Street Bridge in Philadelphia. The Chestnut Street Bridge over the Schuylkill River is on a Pennsylvania Department of Transportation list of 577 bridges that both lack backup protection against collapse in case a single, vital component fails and are designated by inspectors as being in need of repair. Pennsylvania is among the states with the most bridges that are in both of those categories, a combination of red flags that experts say is particularly problematic. State officials say unsafe bridges are promptly closed and that a bridge that is in both categories is not necessarily unsafe. (AP Photo/Matt Rourke)

ADVANCE FOR USE MONDAY, SEPT. 16, 2013 AND THEREAFTER - Cyclists ride beneath the Chestnut Street Bridge that spans the Schuylkill River in Philadelphia on Thursday, Sept. 12, 2013. The Chestnut Street Bridge is on a Pennsylvania Department of Transportation list of 577 bridges that both lack backup protection against collapse in case a single, vital component fails and are designated by inspectors as being in need of repair. Pennsylvania is among the states with the most bridges that are in both of those categories, a combination of red flags that experts say is particularly problematic. State officials say unsafe bridges are promptly closed and that a bridge that is in both categories is not necessarily unsafe. (AP Photo/Matt Rourke)

FILE - In this Wednesday, Aug. 1, 2007 file photo, a police officer approaches a woman sitting on the collapsed decking of the I-35W bridge in Minneapolis. The eight-lane bridge, a major Minneapolis artery, collapsed over the Mississippi River during the evening rush hour earlier that week, killing 13 people and injuring more than 100 others. (AP Photo/StarTribune, Richard Tsong-Taatari, File)

FILE - In this Saturday, Aug. 4, 2007 file photo, vehicles lie in the rubble of the collapsed I-35W bridge in Minneapolis. The bridge had received a "structurally deficient" designation. The National Transportation Safety Board concluded that the cause of the collapse was an error by the bridge's designers, not the deficiencies found by inspectors. A gusset plate, a fracture critical component of the bridge, was too thin. (AP Photo/M. Spencer Green, File)

FILE - In this May 27, 2013 photo provided by the Washington Department of Transportation, a crane removes a pickup truck from the wreckage of the Interstate 5 bridge over the Skagit River in Mount Vernon, Wash. Metal fatigue is evident in a steel truss bridge over Interstate 5 in Washington state - south of this similar steel truss that collapsed on May 23, 2013. The biggest difference between the bridge over the Lewis River and the bridge over the Skagit River is that the span still standing has actually been listed in worse condition. State officials hope to replace it in the next 10 to 15 years. (AP Photo/Washington Department of Transportation)

FILE - In this Thursday, May 23, 2013 photo provided by Francisco Rodriguez, Bryce Kenning sits atop his car that fell into the Skagit River after the collapse of the Interstate 5 bridge minutes earlier in Mount Vernon, Wash. The United States has so many bridges in need of repair or replacement, and so little money to do the work, that state and local officials say they are engaged in a kind of transportation triage: They fix the most important and dangerous spans first, nurse along others and, when theres no hope, shut down the rest. (AP Photo/Francisco Rodriguez, File)

FILE - This Aug. 20, 2012 file photo shows rust on the Tappan Zee Bridge which spans the Hudson River in New York. An Associated Press review of national bridge records found that there are 65,605 structurally deficient bridges across the country, including the Tappan Zee. The state is spending nearly $5 billion to build a new one. (AP Photo/John Minchillo, File)

The Brooklyn Bridge stretches in front of the Manhattan skyline in New York, Thursday, Sept. 12, 2013. The federal government says more than 2,000 New York state bridges are structurally deficient and badly need repairs. That list includes the Brooklyn Bridge, the Tappan Zee Bridge and the Kosciuszko Bridge. (AP Photo/Seth Wenig)

A pickup truck drives on a bridge over Sagamore Creek in Portsmouth, N.H. on Wednesday, Sept. 4, 2013. An Associated Press analysis of 607,380 bridges in the most recent federal National Bridge Inventory showed that 65,605 were classified as "structurally deficient" and 20,808 as "fracture critical." Of those, 7,795 were both - a combination of red flags that experts say indicate significant disrepair and similar risk of collapse. This is one of several in New Hampshire that fall under both categories (AP Photo/Jim Cole)

A patch of cracked concrete exposes reinforcing bars on the Main Ave. bridge from the west side of the Cuyahoga River leading into downtown Cleveland on Tuesday, Sept. 10, 2013. The bridge is one of nearly 340 in Ohio that are both "structurally deficient" and "fracture critical", according to to a national review of bridge records. (AP Photo/Mark Duncan)

The sun sets behind the Frederick Douglass Memorial Bridge over the Anacostia River in Washington on Wednesday, Sept. 4, 2013. Safety concerns about the Douglass bridge, which carries more than 70,000 vehicles a day, are far from unique. An Associated Press analysis of federal data found 7,795 bridges around the country in significant disrepair and at risk of collapse should a single, vital component fail - a combination of red flags that experts say is particularly problematic. (AP Photo/Alex Brandon)